title: Phosphorylation of histone H2AX is a powerful tool for detecting chemical photogenotoxicity.
abstract: Several light-absorbing chemicals are known to show phototoxic effects involving many kinds of DNA damage, and are suspected of initiating skin cancer. In this study, we clarified that phosphorylated histone H2AX (γ-H2AX) (phosphorylated histone H2AX), which was produced with the induction of DNA double-strand breaks, is a sensitive photogenotoxic marker. The immortal human keratinocyte line HaCaT was treated with a library of 11 chemicals (including known strong and weak phototoxic chemicals, and nonphototoxic chemicals) and/or UVA exposure. γ-H2AX was generated after treatments with all phototoxic chemicals and UVA. The limit of detection using γ-H2AX was 100-1,000 times lower than that using cell viability and DNA gel electrophoresis. γ-H2AX was not generated following treatments with nonphototoxic chemicals and UVA. These results indicated that γ-H2AX is a powerful tool for detecting chemical photogenotoxicity.
authors.affiliation: Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan.
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Toyooka
authors.forename: Mio
authors.initials: M
authors.lastname: Ishihama
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ibuki
mesh_terms: D001735:Bithionol / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003374:Coumarins / Q000494:pharmacology; D053903:DNA Breaks, Double-Stranded; D017484:Dermatitis, Phototoxic / Q000175:diagnosis*; D006657:Histones / Q000032:analysis*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects; D008730:Methoxsalen / Q000494:pharmacology; D009152:Mutagenicity Tests / Q000379:methods*; D014466:Ultraviolet Rays
chemical_list: D003374:Coumarins; C468783:H2AX protein, human; D006657:Histones; D001735:Bithionol; C018096:6-methylcoumarin; D008730:Methoxsalen